The rapid aging of China's population poses a serious threat to the country's future growth and social security, and policy actions need to be taken now to deal with the repercussions in the coming decades, said a senior Chinese scholar from Shanghai.

Having overtaken Japan as the world's second-largest economy in 2010, China has followed Japan's path in the graying of its population, which is forecast to also start declining within the coming decade or so, Zuo Xuejin, executive vice president of the Shanghai Academy of Social Sciences and director of the academy's Institute of Economics, said at a recent seminar in Tokyo.

With the world's largest population at 1.34 billion as of 2010, China has seen its total fertility rate — the average number of children born to a woman in her lifetime — fall since the 1970s to hit between 1.4 to 1.5 today — not much different from Japan, Zuo said at the Feb. 20 event organized by the Keizai Koho Center to discuss the nation's demographic challenges and their socioeconomic impacts.